Title: State and Local Efforts to Reduce Greenhouse Gas Emissions from
Vehicles

Description: Greenhouse gas emissions are a major contributor to climate
change. The largest source of emissions in the U.S. is transportation
occurring on our nation's roadways, which are owned and run by state and
local governments. We learn more about the role of state and local
governments in reducing greenhouse gas emissions from vehicles from
GAO's Biza Repko.

Related GAO Work: GAO-23-106022, Climate Change: State and Local Efforts
to Reduce Greenhouse Gas Emissions from Vehicles

Released: August 2023

[Music]

[Biza Repko:] States and local governments really have a vital role to
play to reduce those on-road greenhouse gas emissions and meeting
reduction targets.

[Holly Hobbs:] Hi and welcome to GAO's Watchdog Report. Your source for
fact-based, nonpartisan news and information from the U.S. Government
Accountability Office. I'm your host, Holly Hobbs. Greenhouse gas
emissions are a major contributor to climate change. When we drilldown
on where these gases are coming from, we find that the largest source in
the U.S. is transportation and that the vast majority of these emissions
occur on our nation's roadways, which are owned and run by state and
local governments. In a new report out today, we looked at the role of
state and local governments in reducing greenhouse gas emissions from
vehicles and the actions they are taking to do so. Here to tell us more
is GAO's Biza Repko, a transportation expert. Thanks for joining us.

[Biza Repko:] Happy to be here.

[Holly Hobbs:] So Biza, what is the role of state and local governments
in reducing greenhouse gas emissions, and how are they doing it?

[Biza Repko:] So, you know, as you were talking about before, state and
local governments really do play a key role in implementing activities
to reduce those transportation-related greenhouse gas emissions. States
and local governments--and organizations that are known as Metropolitan
Planning Organizations, or MPOs--they have different policies and they
may have different degrees of emphasis on reducing greenhouse gas
emissions. But we really found three major types of actions. And those
actions are those to estimate emissions, analyze the effects of
emissions on investments, and set targets to reduce emissions.

[Holly Hobbs:] So maybe you could walk us through that. Starting with
estimating emissions. How are they doing that?

[Biza Repko:] So, our review found examples of states and local
governments that were using different types of data to estimate those on
road greenhouse gas emissions. Most of them rely on annual traffic count
data, and that data looks at vehicle miles traveled. But there's others
that told us they estimated emissions using data that they derived from
more complex modeling tools. There's a number of them that use a tool
provided by the EPA that's called the MOVES tool. And in a different
example, California officials told us that they developed their own
model that estimates emissions; and it uses 28 sources of data to track
those emissions.

[Holly Hobbs:] You said they're also looking at how transportation
investments might impact greenhouse gas emissions. Could you give us an
example?

[Biza Repko:] So we talked to some officials from the Boston
Metropolitan Planning Organization, and they told us that they try for
every project they fund to estimate the emissions and where possible,
they try to quantify that. So if you're looking at something like an
intersection improvement--think of something like a roundabout or a
traffic management system--the officials try to examine the project and
estimate how it could contribute to emissions reductions. They also told
us when they're planning which projects they want to fund, they score
them on various criteria. But one of those criteria is the extent to
which the project reduces greenhouse gas emissions. So for them and
their organization, when they're making funding decisions, the relative
ranking or priority of a project may depend in part on the annual
estimated changes in carbon dioxide emissions that could result.

[Holly Hobbs:] And the last sort of bucket we found on state and local
efforts was that some had set emissions reduction goals, right? How are
they doing that, and how are they tracking progress toward goals? 

[Biza Repko:] So one example is the District of Columbia. In June 2022,
the D.C. Metropolitan Planning Organization set targets, and those
targets were to reduce on road greenhouse gas emissions 50% from 2005
levels by 2030 and 80% by 2050. And along with that, they adopted
strategies to achieve those targets and those strategies are things like
deploying a region-wide charging network for electric vehicles and
improving pedestrian or bike access to high capacity transit stations.

[Holly Hobbs:] And we looked at several states' and cities' efforts to
reduce emissions. Not just D.C. Did we see a lot of variation in their
efforts?

[Biza Repko:] We did. You know, we did purposely look at a mix of states
and planning organizations just to make sure that we could get a sense
of the range of activities. And so, some of the states or metropolitan
planning organizations didn't engage in these activities. One example is
the Montana Department of Transportation. They told us that they don't
track or estimate on road greenhouse gas emissions because the majority
of roads under their jurisdiction are rural, and they don't have
congestion issues. But even if you're looking at those states that do
estimate or do set targets for on road greenhouse gas emissions, there
was a wide variety of approaches. One example is Colorado, and all of
the metropolitan planning organizations in that state have established
specific on road greenhouse gas emission targets. But there's other
states like Virginia or Michigan that have targets for emissions
reductions across the entire state, across all their economic sectors,
rather than just transportation specific.

[Holly Hobbs:] So what about the challenges in meeting their goals? What
did states and cities tell us about that?

[Biza Repko:] You know when it related to estimating, most of the states
and planning organizations we interviewed agreed that calculating
emissions is not all that difficult. But they did say there may be some
staff capacity or data availability challenges. As it relates to
investments, the selected states and metropolitan planning organizations
commonly talk to us about challenges that are related to how do you
reliably quantify the effects of a specific investment. For example,
folks from the Colorado Department of Transportation told us it's really
difficult to model an investment and evaluate its effects over time. For
example, you know, they said what is the effect of estimating adding one
mile of bike lane on greenhouse gas emissions 10 years later. Related to
targets, most of the states and MPO officials that we talked to talked
about challenges in meeting those targets, such as they really don't
have ways to incentivize consumers to adopt particular fuels or vehicles
that might be very effective in reducing emissions. And they also told
us that some investments to reduce emissions may not be considered cost
effective. So one example of that is transit projects, which can really
help reduce the number of vehicle miles traveled and therefore
greenhouse gas emissions require significant funding and planning. And
there's challenges constructing and operating in maintaining them.

{MUSIC}

[Holly Hobbs:] Biza just told us that the number and types of steps
taken by cities and states to reduce greenhouse emissions from vehicles
vary. And that transportation officials we interviewed have also
identified a number of challenges in their efforts.  So Biza, we have a
lot of work on addressing climate change and on transportation issues.
How does this report fit into that?

[Biza Repko:] so changes in the climate, of course, pose a risk to our
environment, but they also pose a risk to the safety and reliability of
the U.S. transportation system. And so this report on state and local
activities is really part of GAO's broader examination of climate
issues, which includes reporting on efforts like reducing the risk of
climate disasters by measuring and setting targets and also reporting on
efforts to enhance the resilience of transportation infrastructure, such
as highways or transit, to better respond to climate change.

[Holly Hobbs:] And last question. What's the bottom line of this report?

[Biza Repko:] Well, transportation is the largest source of U.S.
greenhouse gas emissions. And states and local governments, which own a
lot of the roads where these emissions take place, really have a vital
role to play. And these organizations have taken a variety of approaches
to reduce this on road greenhouse gas emissions. But they do face
challenges measuring the outcomes of their efforts and meeting reduction
targets.

[Holly Hobbs:] That was Biza Repko talking about our new report on
greenhouse gas emissions from vehicles. Thanks for your time, Biza.

[Biza Repko:] Thanks for having me.

[Holly Hobbs:] And thank you for listening to the Watchdog Report. To
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